Lossy data conversion

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A lossy data conversion method is one where converting data between one storage format and another displays data in a form that is "close enough" to be useful, but may differ in some ways from the original. This type of conversion is used frequently between software packages that rely on different storage techniques. In many cases, a software package such as Microsoft Word will enable a document stored in one format to be saved as another, in particular HTML. The document saved in the lossy format may look identical, but the conversion can also cause some loss of fidelity or functionality.

Data conversion is the conversion of computer data from one format to another. Throughout a computer environment, data is encoded in a variety of ways. For example, computer hardware is built on the basis of certain standards, which requires that data contains, for example, parity bit checks. Similarly, the operating system is predicated on certain standards for data and file handling. Furthermore, each computer program handles data in a different manner. Whenever any one of these variables is changed, data must be converted in some way before it can be used by a different computer, operating system or program. Even different versions of these elements usually involve different data structures. For example, the changing of bits from one format to another, usually for the purpose of application interoperability or of capability of using new features, is merely a data conversion. Data conversions may be as simple as the conversion of a text file from one character encoding system to another; or more complex, such as the conversion of office file formats, or the conversion of image formats and audio file formats.

Microsoft Word Word processor developed by Microsoft

Microsoft Word is a word processor developed by Microsoft. It was first released on October 25, 1983 under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platforms including IBM PCs running DOS (1983), Apple Macintosh running the Classic Mac OS (1985), AT&T Unix PC (1985), Atari ST (1988), OS/2 (1989), Microsoft Windows (1989), SCO Unix (1994), and macOS.

HTML Hypertext Markup Language

Hypertext Markup Language (HTML) is the standard markup language for creating web pages and web applications. With Cascading Style Sheets (CSS) and JavaScript, it forms a triad of cornerstone technologies for the World Wide Web.

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Types of lossy conversion

There are three basic types of lossy data conversion:

IBM American multinational technology and consulting corporation

International Business Machines Corporation (IBM) is an American multinational information technology company headquartered in Armonk, New York, with operations in over 170 countries. The company began in 1911, founded in Endicott, New York, as the Computing-Tabulating-Recording Company (CTR) and was renamed "International Business Machines" in 1924.

In computing, just-in-time (JIT) compilation is a way of executing computer code that involves compilation during execution of a program – at run time – rather than prior to execution. Most often, this consists of source code or more commonly bytecode translation to machine code, which is then executed directly. A system implementing a JIT compiler typically continuously analyses the code being executed and identifies parts of the code where the speedup gained from compilation or recompilation would outweigh the overhead of compiling that code.

Other types of data

Graphic data (images) is often converted from one data storage format to another. Such conversions are usually described separately as either lossy data compression or lossless data compression.

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